Sockets for “springed” semiconductor devices

ABSTRACT

Temporary connections to spring contact elements extending from an electronic component such as a semiconductor device are made by urging the electronic component, consequently the ends of the spring contact elements, vertically against terminals of an interconnection substrate, or by horizontally urging terminals of an interconnection substrate against end portions of the spring contact elements. A variety of terminal configurations are disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Continuation of application of Ser. No. 09/519,279, filed Mar.7, 2000 now U.S. Pat. No. 6,232,149 which is a continuation of Ser. No.09/103,163 filed Jun. 30, 1998 now Pat. No. 6,033,935 which claimsbenefit of Ser. No. 60/051,365 filed Jun. 30, 1997.

TECHNICAL FIELD OF THE INVENTION

The invention relates to making interconnections between electroniccomponents, especially microelectronic components and, moreparticularly, to interconnection elements (contact structures)exhibiting resiliency (springiness), and methods of making same.

BACKGROUND OF THE INVENTION

Commonly-owned U.S. patent application Ser. No. 08/152,812 filed Nov.16, 1993 (now U.S. Pat. No. 4,576,211, issued Dec. 19, 1995), and itscounterpart commonly-owned copending “divisional” U.S. patentapplications Ser. No. 08/457,479 filed Jun. 1, 1995 (status: pending)and U.S. patent application Ser. No. 08/570,230 filed Dec. 11, 1995(status: pending), all by KHANDROS, disclose methods for makingresilient interconnection elements for microelectronics applicationsinvolving mounting an end of a flexible elongate core element (e.g.,wire “stem” or “skeleton”) to a terminal on an electronic component,coating the flexible core element and adjacent surface of the terminalwith a “shell” of one or more materials having a predeterminedcombination of thickness, yield strength and elastic modulus to ensurepredetermined force-to-deflection characteristics of the resultingspring contacts. Exemplary materials for the core element include gold.Exemplary materials for the coating include nickel and its alloys. Theresulting spring contact element is suitably used to effect pressure, ordemountable, connections between two or more electronic components,including semiconductor devices.

Commonly-owned, copending U.S. patent application Ser. No. 08/340,144filed Nov. 15, 1994 and its corresponding PCT Patent Application No.PCT/US94/13373 filed Nov. 16, 1994 (WO95/14314, published May 26, 1995),both by KHANDROS and MATHIEU, disclose a number of applications for theaforementioned spring contact elements, and also discloses techniquesfor fabricating contact pads (contact tip structures) at the ends of thespring contact elements.

Commonly-owned, copending U.S. patent application Ser. No. 08/452,255filed May 26, 1995 and its corresponding PCT Patent Application No.PCT/US95/14909 filed Nov. 13, 1995 (WO96/17278, published Jun. 6, 1996),both by ELDRIDGE, GRUBE, KHANDROS and MATHIEU, disclose additionaltechniques and metallurgies for fabricating spring contact elements ascomposite interconnection structures and for fabricating and mountingcontact tip structures to the free ends (tips) of the compositeinterconnection elements.

Commonly-owned, copending U.S. patent application Ser. No. 08/558,332filed Nov. 15, 1995 by ELDRIDGE, GRUBE, KHANDROS and MATHIEU, and itscorresponding PCT Patent Application No. US95/14885 filed Nov. 15, 1995by ELDRIDGE, GRUBE, KHANDROS and MATHIEU disclose methods of fabricatingresilient contact structures which are particularly well-suited tofabricating spring contact elements directly on semiconductor devices.As used herein, a semiconductor device having spring contact elementsmounted thereto is termed a “springed semiconductor device”.

Commonly-owned, copending U.S. Provisional Patent Application No.60/024,555 filed Aug. 26, 1996, by ELDRIDGE, KHANDROS and MATHIEU, andPCT Patent Application No. US97/08606 filed May 15, 1997 by DOZIER,ELDRIDGE, KHANDROS, MATHIEU and TAYLOR disclose additional contact tipstructure metallurgies and structures.

The present invention addresses and is particularly well-suited tomaking interconnections to modern microelectronic devices having theirterminals (bond pads) disposed at a fine-pitch. As used herein, the term“fine-pitch” refers to microelectronic devices that have their terminalsdisposed at a spacing of less than 5 mils, such as 2.5 mils or 65 μm. Aswill be evident from the description that follows, this is preferablyachieved by taking advantage of the close tolerances that readily can berealized by using lithographic rather than mechanical techniques tofabricate the contact elements.

BRIEF DESCRIPTION (SUMMARY) OF THE INVENTION

As mentioned above, a semiconductor device having spring contactelements mounted thereto is termed a “springed semiconductor device”.Such a device may be interconnected to an interconnection substrate inone of two main ways. It may be “permanently” connected such as bysoldering the free ends of the spring contact elements to correspondingterminals on an interconnection substrate such as a printed circuitboard. Alternatively, it may be “temporarily” connected to the terminalssimply by urging the springed semiconductor device against theinterconnection substrate so that a pressure connection is made betweenthe free ends of the spring contact elements and the terminals. Anotherway of looking at such temporary pressure connections is that thespringed semiconductor device is “self-socketing”.

The ability to remove a springed semiconductor device from its temporarypressure connection with an interconnection substrate is certainlyuseful in the context of replacing or upgrading the springedsemiconductor device. In this context, it is important that the pressureconnections be robust, and capable of withstanding the wear and tearassociated with normal operations. Generally, a certain minimum contactforce is desired to effect reliable pressure contact to electroniccomponents (e.g., to terminals on electronic components). For example, acontact (load) force of approximately 15 grams (including as little as 2grams or less and as much as 150 grams or more, per contact) may bedesired to ensure that a reliable electrical connection is made to aterminal of an electronic component which may be contaminated with filmson its surface, or which has corrosion or oxidation products on itssurface. The minimum contact force required of each spring contactelement demands either that the yield strength of the spring material orthat the size of the spring element are increased. As a generalproposition, the higher the yield strength of a material, the moredifficult it will be to work with (e.g., punch, bend, etc.). And thedesire to make springs smaller essentially rules out making them largerin cross-section.

A more fundamental object is achieved simply by making transient (verytemporary) connections to a springed semiconductor device. And that is,the ability to test the springed semiconductor device prior totemporarily or permanently mounting it to an interconnection substrateof a system to (1), if necessary, burn-in the springed semiconductordevice and (2) to ascertain whether the springed semiconductor device ismeasuring up to its specifications. As a general proposition, this canbe accomplished by making “transient” pressure connections with thespring contact elements with relaxed constraints on contact force andthe like. The making of such transient connections to springedsemiconductor devices is the focus of the present invention. The presentinvention discloses a number of techniques for socketing (makingtransient pressure connections) to springed semiconductor devices.

According to the invention, methods and apparatuses for effecting atemporary connection to a portion of an elongate spring contact elementmounted to and extending from an electronic component are provided.

In one embodiment, an interconnection substrate has a terminal which isa plated through hole. The spring contact element is inserted throughthe through hole so that a portion of the spring contact element iswithin the through hole.

Additional methods, apparatuses and embodiments thereof are disclosedherein.

Other objects, features and advantages of the invention will becomeapparent in light of the following description thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will be made in detail to preferred embodiments of theinvention, examples of which are illustrated in the accompanyingdrawings. The drawings are intended to be illustrative, not limiting.Although the invention will be described in the context of thesepreferred embodiments, it should be understood that it is not intendedto limit the spirit and scope of the invention to these particularembodiments. Certain elements in selected ones of the drawings areillustrated not-to-scale, for illustrative clarity. Often, similarelements throughout the drawings are referred to by similar referencesnumerals. For example, the element 199 may be similar in many respectsto the element 299 in another figure. Also, often, similar elements arereferred to with similar numbers in a single drawing. For example, aplurality of elements 199 may be referred to as 199 a, 199 b, 199 c,etc.

FIG. 1 is a side cross-sectional view of a “springed” semiconductordevice, according to the invention.

In the following figures, a springed semiconductor device is shown withspring contact elements which are mounted thereto and extend therefromcontacting corresponding terminals of an interconnection substrate. Insome of the figures, the spring contact elements are shown contactingthe terminals. Other of the figures are slightly exploded forillustrative clarity, showing the spring contact elements nearly incontact with the terminals.

FIG. 2 is a side cross-sectional view of a “springed” semiconductordevice being urged against an interconnection substrate such as aprinted circuit board (PCB), according to the invention.

FIG. 2A is a side cross-sectional view of another technique of urging aspringed semiconductor device against an interconnection substrate,according to the invention.

FIG. 3 is a side cross-sectional view of another technique of urging aspringed semiconductor device into contact with terminals of aninterconnection substrate, according to the invention.

FIG. 4 is a side cross-sectional view of another technique of connectinga springed semiconductor device to terminals of an interconnectionsubstrate, according to the invention.

FIG. 5A is a side cross-sectional view of a technique of urging aspringed semiconductor device into contact with concave terminals of aninterconnection substrate, according to the invention.

FIG. 5B is a side cross-sectional view of another technique of urging aspringed semiconductor device into contact with concave terminals of aninterconnection substrate, according to the invention.

FIG. 5C is a side cross-sectional view of another technique of urging aspringed semiconductor device into contact with concave terminals of aninterconnection substrate, according to the invention.

FIG. 6A is a side cross-sectional view of another technique ofhorizontally contacting spring contact elements extending from aspringed semiconductor device with resilient contact structuresextending from terminals of an interconnection substrate, according tothe invention.

FIG. 6B is a bottom plan view of the apparatus of FIG. 6A, according tothe invention.

FIG. 7A is a side cross-sectional view of another technique ofhorizontally contacting spring contact elements extending from aspringed semiconductor device with pairs of resilient contact structuresextending from terminals of an interconnection substrate, according tothe invention.

FIG. 7B is a bottom plan view of the apparatus of FIG. 7A, according tothe invention.

FIG. 7C is a bottom plan view of an alternate embodiment of theapparatus of FIG. 7A, according to the invention.

FIG. 8 is a side cross-sectional view of another technique ofhorizontally contacting spring contact elements extending from aspringed semiconductor device with terminals of an interconnectionsubstrate, according to the invention.

FIGS. 9A and 9B are side cross-sectional views of another technique ofhorizontally contacting spring contact elements extending from aspringed semiconductor device with terminals of an interconnectionsubstrate, according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a “springed” semiconductor device 102, which is anelectronic component having a plurality (two of many shown) offree-standing elongate microspring spring contact structures 110 mountedto and extending from a corresponding plurality (two of many shown) ofterminals 104 on a surface thereof. Each spring contact element 110extends laterally parallel to the surface of the component 102 (in the“x” and “y” axes, and extends to a height “H” in the z-axis above thesurface of the component 102.

As discussed in a number of the aforementioned patents and patentapplications, the springed semiconductor device 102 can be connected toanother electronic component such as a printed circuit board (PCB) orother suitable interconnection substrate simply by urging the free ends(tips) 110 a of the spring contact elements 110 against correspondingterminals (not shown) on the PCB (not shown) Alteratively, the free ends(tips) of the spring contact elements 110 can be soldered to theterminals of the PCB or interconnection substrate.

FIG. 2 illustrates a technique 200 wherein the “springed” semiconductordevice 102 is urged (in the direction of the arrow 212) against aninterconnection substrate such as a printed circuit board (PCB) 214 sothat the tips 110 a come into pressure contact with a correspondingplurality (two of many shown) of terminals 216 on the PCB 214 toestablish a pressure connection therewith. As mentioned above, the tips110 a of the spring contact elements 110 can also be soldered to theterminals 216 of the PCB 214. The present invention, however, isprincipally directed to making temporary connections with the springcontact elements (110) of springed semiconductor devices (102).

FIG. 2, and the figures that follow, are illustrative of makingtemporary pressure connections to a springed semiconductor device suchas for testing the semiconductor device. In this context, thesemiconductor device is termed a “device under test” (DUT). In some ofthe figures, such as in FIG. 2, the temporary pressure connection ismade in the z-axis, by applying “vertical” pressure to the tip (110 a)of the spring contact element (110) in a direction which isperpendicular to the surface of the electronic component 102. In otherof the figures, such as in FIG. 6A, the temporary pressure connection ismade in the x or y axes, by applying “horizontal” pressure to amidportion of the spring contact element (110) in a direction which isparallel to the surface of the electronic component 102.

FIG. 2A illustrates another technique 220 for making a verticaltemporary pressure connection with spring contact elements 110 of aspringed semiconductor device (DUT) 102. In a manner similar to that ofthe technique illustrated in FIG. 2, the tips 110 a of the springcontact elements 110 make pressure connections (contact) with terminals226 (compare 216) of a PCB 224 (compare 214), as illustrated by thearrow 228 (compare 212). In this example, the DUT 102 is housed within ametal cap (housing) 230 which is a five-sided box such that the backside (top, as viewed) of the DUT is against the bottom surface of thehousing 230. The open (bottom, as viewed) end of the housing 230 iscovered by a rigid planar member (substrate) 232 which has a plurality(two of many shown) of guide holes 234 aligned with the tips 110 a ofthe spring contact elements 110 which extend therethrough. For example,for spring contact elements 110 having a height “H” of 50 mils, thespring contact elements 110 extend 5 mils beyond the external (bottom,as viewed) surface of the rigid planar substrate 232.

The rigid planar substrate 232 is suitably formed of silicon and theguide holes are suitably tapered with their wide ends facing the DUT 102and the interior of the housing 230, and is suitably formed of a siliconwafer using conventional semiconductor micromachining techniques. Asillustrated, the rigid planar substrate 232 is sized to extend slightly,such as 100-250 mils beyond the four (two visible in the figure)sidewalls of the housing 230, to completely cover the open (bottom, asviewed) end of the housing 230. In this manner, the DUT 102 and a majorportion of each spring contact element 110 are protected frominadvertent mechanical damage, such as from handling this springedsemiconductor device “subassembly” (102, 110, 232).

As illustrated in FIG. 2A, the subassembly of the DUT 102 within thehousing 230 is held against the front (top, as viewed) surface of thePCB 224 by suitable mechanical means, such as spring clips 236 havingtwo ends, one end 236 a extending into or through corresponding holes238 in the PCB 224, the other end 236 b extending over the externalbottom (top, as viewed) surface of the housing 230. In this manner, areliable desired amount of pressure can be effected between the springcontact elements 110 and corresponding terminals 226 of the PCB 224.Such an arrangement is suitable for testing (transient connection) orfor more permanent demountable mounting of the subassembly (102/230) tothe PCB.

In summary, there has been described in FIGS. 2 and 2A a method ofeffecting temporary connections to free ends (tips) of elongate springcontact elements mounted to and extending from an electronic componentsuch as a semiconductor device by:

urging the springed semiconductor device (DUT) against aninterconnection substrate (e.g., PCB) so that the tips of the springcontact elements vertically contact corresponding terminals on the PCB.

Another Vertical Technique

Commonly-owned, copending PCT Patent Application No. US95/14842 filedNov. 13, 1995 by Dozier, Eldridge, Grube, Khandros and Mathieu [C-5-PCT]discloses methods of removably mounting electronic components to acircuit board (interconnection substrate) by providing a socket elementwith solder contacts on one side thereof and with elongate free-standingspring contact elements on another side thereof, particularly for makingpressure connections to corresponding balls and lands of ball grid array(BGA) and land grid array (LGA) electronic components.

FIG. 3 illustrates another technique 300 of making vertical pressureconnections to tips of spring contact elements 110 of a springedsemiconductor device (DUT) 102. Whereas in the techniques described withrespect to FIGS. 2 and 2A the interconnection substrate (214, 224)simply had terminals against which the tips (110 a) of the springcontact elements (110) were pressed, in this technique, the tips 110 aof the spring contact elements 110 are pressed against terminals 326(compare 216) which are disposed at and joined to the free ends 310 a offree standing resilient contact structures 310 (compare 110) which aremounted to and extend from corresponding terminals 316 (compare 216) ofan interconnection substrate 314 (compare 214). In this manner, theterminals 326 are yielding in the z-axis. The DUT 102 is moved in thedirection indicated by the arrow 312 (compare 212) to effect theconnection(s).

The terminals 326 of the resilient contact structures 310 are formed inany suitable manner, such as has been described with respect to joiningprefabricated contact tip structures to free ends of elongate resilientcontact structures described, for example, in commonly-owned PCT PatentApplication Nos. US96/08107 filed May 24, 1996 by Eldridge, Khandros andMathieu [C-14-PCT] and US97/08606 filed May 15, 1997 by Dozier,Eldridge, Khandros, Mathieu and Taylor [C-17-PCT], and may be providedwith any suitable metallurgy and topology (surface flatness and texture)to optimize pressure connections being made between the terminals 326and the ends 110 of the spring contact elements 110. The terminals 326are suitably “pads” having a cross-dimension (e.g., diameter) of 8-10mils and are joined to the ends of the elongate resilient contactstructures 310 which have a smaller cross-dimension (diameter) such as4-6 mils.

In a manner similar and comparable to that of the housing 230 (see FIG.2A) a rigid planar substrate 332 (compare 232) is disposed parallel tothe surface of the interconnection substrate 314 at a distance from itssurface which is sufficient to be just above the terminals 326, and isprovided with holes 334 (compare 234) therethrough which are alignedwith the terminals 326. The substrate 332 is maintained in this positionby suitable spacers 338 which may be a single, rigid, square, rigidring-like structure which is comparable to the socket body (332) of theaforementioned US95/14842 [C-5-PCT]. In a manner similar to thatdescribed hereinabove with respect to FIG. 2A, the rigid structure 332is suitably formed of a silicon wafer using conventional semiconductormicromachining techniques so that the holes 334 are tapered, with theirwider opening on the exterior (top, as viewed) surface of the rigidsubstrate 332.

Suitably dimensioned, the “socket” formed by the interconnectionsubstrate 314, the resilient contact structures 310 having pads 326mounted at their ends, and the rigid substrate 332 having holes 334aligned with the pads 326 can serve as a socket for a ball grid array(BGA) package (not shown) rather than as a socket for a springedsemiconductor device 102.

In this manner, there is provided a test socket for making temporarypressure connections to tips of elongate contact structures extendingfrom a DUT by:

providing a plurality of elongate free-standing resilient contactstructures from corresponding terminals on an interconnection substrate,each of said resilient contact structures being provided with “floating”terminals at their free ends for receiving tips of the elongate contactstructures extending from the DUT.

Another Technique

FIG. 4 illustrates another technique 400 of effecting pressureconnections to elongate spring contact elements 110 mounted to andextending from a semiconductor device 102. This technique is neitherstrictly vertical (as is the case with the techniques describedhereinabove) or horizontal (as is the case with the techniques describedhereinbelow).

In this technique, end portions (commencing at the ends 110 a andextending along the spring contact elements 110) of the spring contactelements 110 are inserted into plated through hole terminals 416(compare 216) of an interconnection substrate 414 (compare 214) such asa printed circuit board. With a suitable, such as “wavy” shape to theend portions of the spring contact elements 110, a pressure connectionmay be effected between the spring contact elements 110 and theterminals 416. The semiconductor device 102 is moved in a directionindicated by the arrow 412 (compare 212) to effect the connection(s).

This technique of “plugging” the end portions of the spring contactelements 110 into plated through holes is very amenable to subsequentlysoldering the springed semiconductor device 102 in place on the PCB 414.The springed semiconductor device 102 could subsequently be removed(e.g., for replacement) simply by heating to melt the solder, cleaningthe through holes, and reinserting and soldering into place anotherspringed semiconductor device.

In this manner, there is provided a socketing technique makingconnections with end portions of elongate contact structures extendingfrom a semiconductor device by:

providing a plurality of terminals which are plated through holes in aninterconnection substrate; and

plugging the end portions of the elongate contact structures into thethrough holes; and

optionally, soldering the elongate contact structures to the terminals.

Another Vertical Technique

FIGS. 5A, 5B and 5C illustrates other techniques 500, 520 and 530,respectively, of effecting pressure connections to elongate springcontact elements 110 mounted to and extending from a semiconductordevice 102. This technique effects a vertical pressure connectionbetween concave terminals of an interconnection substrate and the tips110 a of the spring contact elements 110 extending from the DUT 102.

As shown in FIG. 5A, the ends 110 a of the spring contact elements 110)of the spring contact elements 110 are brought vertically, as indicatedby the arrow 512 (compare 212), into contact with corresponding ones ofa plurality (two of many shown) of terminals 516 (compare 216) of aninterconnection substrate 514 (compare 214). The terminals 516 areconcave. In this example, the terminals 516 are formed like platedthrough holes (compare 416) that have an upper portion in the form of acone or pyramid which has its base at an upper (top, as viewed) surfaceof the interconnection substrate 514 and its apex (point) within theinterconnection substrate 514.

As shown in FIG. 5B, the ends 110 a of the spring contact elements 110)of the spring contact elements 110 are brought vertically, as indicatedby the arrow 522 (compare 212), into contact with corresponding ones ofa plurality (two of many shown) of terminals 526 (compare 216) of aninterconnection substrate 524 (compare 214). The terminals 526 areconcave. In this example, the terminals 526 are formed like platedthrough holes (compare 416) that have an upper portion in the form of ahemisphere which has its base at an upper (top, as viewed) surface ofthe interconnection substrate 524 and its apex within theinterconnection substrate 524.

As shown in FIG. 5C, the ends 110 a of the spring contact elements 110)of the spring contact elements 110 are brought vertically, as indicatedby the arrow 532 (compare 212), into contact with corresponding ones ofa plurality (two of many shown) of terminals 536 (compare 216) of aninterconnection substrate 534 (compare 214). The terminals 536 areconcave. In this example, the terminals 536 are formed like platedthrough holes (compare 416) that have an upper portion in the form of atrapezoidal solid which has relatively wider base portion at an upper(top, as viewed) surface of the interconnection substrate 534 and itsrelatively shorter base portion within the interconnection substrate534.

This is comparable in some regard to the aforementioned technique (seeFIG. 4) of “plugging” the end portions of the spring contact elements110 into plated through holes, but relies entirely on vertical pressureto effect the desired contact between the DUT 102 and the terminals 516,526, 536 of the interconnection substrates 514, 524, 534, respectively.In each of the examples of FIGS. 5A, 5B and 5C, the tip 110 a of thespring contact structure 110 enters the concave terminal 516, 526, 536at its widest portion, thus “capturing” the ends 110 a of the springcontact elements 110 with the terminals.

In this manner, there is provided a socketing technique makingconnections with end portions of elongate contact structures extendingfrom a semiconductor device by:

providing a plurality of concave terminals on an interconnectionsubstrate, each of the concave terminals having a widest portion at asurface of the interconnection substrate; and

pressing the tips of the elongate contact structures into the concaveterminals.

A Horizontal Pressure Technique

There have been described hereinabove a number of techniques foreffecting temporary pressure connections to elongate spring contactelements (110) of a springed semiconductor device (102) by applyingpressure vertically (normal to the surface of the component 102) to thetips (110 a) of the spring contact elements (110). In certain instances,this can cause the spring contact elements (110) to become permanently(plastically) deformed in the z-axis. It is thus desirable to provide atechnique for making a “z-less” or low insertion force socket forcontacting the elongate spring contact elements (110) of springedsemiconductor devices (102). Hence, there are described hereinbelow anumber of techniques for making temporary pressure connections toelongate spring contact elements (110) of a springed semiconductordevice (102) by applying pressure horizontally (parallel to the surfaceof component 102) to end portions of the spring contact elements (110).

FIGS. 6A and 6B illustrate a technique 600 for making temporary pressureconnections to elongate spring contact elements 110 of a springedsemiconductor device (DUT) 102. The tips 110 a of the elongate springcontact elements 110 extend through a plurality (two of many shown) ofholes 634 (compare 334) through a rigid substrate 632 which iscomparable to the aforementioned rigid substrate 332 in that the rigidsubstrate 632 formes a protective cover for elongate rigid contactstructures 610 (compare 310) mounted to and extending from terminals 616(compare 316) on an interconnection substrate 614 (compare 314). Theinterconnection substrate 614 is supported below the rigid substrate 632by a spacer 638 (compare 338) such as a square ring. Also, a bodyportion 640 of the socket has sidewalls which extends from the lower(bottom, as viewed) surface of the rigid substrate, around the peripheryof the interconnection substrate 614, to the bottom surface of theinterconnection substrate 614 just within its periphery. Theinterconnection substrate 614 may be provided with resilient contactstructures (not shown) on its bottom (as viewed) surface to makepressure connections to yet another interconnection substrate (notshown) such as a printed circuit board (PCB).

In contrast to the resilient contact structures 310 which are primarilyoriented normal to the surface of the interconnection substrate 314 tomake vertical pressure connections to the ends 110 a of the springcontact elements 110, in this technique the resilient contact structures610 mounted to and extending from the terminals 616 of theinterconnection substrate 614 extend primarily parallel to the surfaceof the interconnection substrate 614 so as to make horizontal pressureconnections to end portions of the spring contact elements 110. Asviewed in FIG. 6A, an end portion of each resilient contact structure630 is positioned to extend horizontally across an end portion of acorresponding one of the spring contact elements 110. Stated anotherway, the tip 110 a of each spring contact element 110 extends beyond thehorizontal end portion of a corresponding one of the resilient contactstructures 630. As best viewed in FIG. 6B, this ensures that the endportions of the resilient contact structures 630 will resiliently urgeagainst the end portions of the spring contact elements 110 when theinterconnection substrate 614 is moved in a direction shown by the arrow612 (compare 312) which is parallel to the surfaces of the DUT 102 andthe interconnection substrate 614. In other words, they “criss-cross”one another.

In this manner, a technique is provided for making connections with endportions of elongate contact structures extending from a semiconductordevice by:

urging end portions of elongate resilient contact structures mounted toand extending from terminals on an interconnection substratehorizontally against end portions of spring contact elements mounted toand extending from a semiconductor device.

Another Horizontal Pressure Technique

In the previously-described technique, a single resilient contactstructure (610), the end portion of which is horizontally (parallel tothe interconnection substrate) oriented, criss-crosses and contacts anend portion of a single spring contact element (110) extendingvertically from a semiconductor device (102) with a contact force whichis horizontal.

FIGS. 7A, 7B and 7C illustrate another horizontal pressure technique 700wherein a pair of (two) generally parallel spaced-apart resilientcontact structures 710 and 711 (compare 610) make horizontal contactwith an end portion of a spring contact element 110 extending from aspringed semiconductor device 102.

As best viewed in FIGS. 7 and 7A, a pair of two spaced-apart resilientcontact structures 710 and 711 extend from a single terminal 716(compare 616) on a bottom (as viewed) surface of an interconnectionsubstrate 714 across a hole 734 (compare 634) through theinterconnection substrate 714. An end portion of a corresponding one ofthe spring contact elements 110 extending from the semiconductor device102 extends through the hole 734 beyond the resilient contact structures710 and 711 (i.e., past their z-axis coordinate) at a position which isslightly inward from the ends 710 a and 711 a of the resilient contactstructures 710 and 711, respectively.

In the embodiment of FIG. 7B, the two resilient contact structures 710and 711 are spaced apart a distance (e.g., 3 mm) which is less than thethickness or diameter (e.g., 5 mm) of the end portion of the springcontact element 110 being captured (pinched) at the position where theywill grab the spring contact element 110 and are shaped as follows. Theyoriginate from (are mounted to) the same terminal 716 at a distance(e.g. 5 mm) apart from one another, then curve slightly (e.g., 1 mm)outward (away from one another), then curve back towards one another soas to be spaced less than the diameter of the spring contact element 110from one another, then curve outwards again to provide a “tapered” entryfor the spring contact element 110 to slip past their tips 710 and 711into the gap between the two generally parallel resilient contactstructures 710 and 711 when the terminal 716 (i.e., the interconnectionsubstrate 714) is moved in the horizontal direction indicated by thearrow 712 (compare 612).

In the embodiment of FIG. 7C, the two resilient contact structures 710′and 711′ are spaced apart a distance (e.g., 3 mm) which is less than thethickness or diameter (e.g., 5 mm) of the end portion of the springcontact element 110 being captured (pinched) at the position where theywill grab the spring contact element 110 and are shaped as follows. Theyoriginate from (are mounted to) the same terminal 716′ at a distance(e.g. 5 mm) apart from one another, then curve slightly (e.g., 1 mm)inward (towards from one another), then curve outwards again to providea “tapered” entry for the spring contact element 110 to slip past theirtips 710′ and 711′ into the gap between the two generally parallelresilient contact structures 710′ and 711′ when the terminal 716 (i.e.,the interconnection substrate 714) is moved in the horizontal directionindicated by the arrow 712 (compare 612).

In this manner, a technique is provided for making connections with endportions of elongate contact structures extending from a semiconductordevice by:

capturing an end portion of a spring contact element mounted to andextending from a semiconductor device between end portions of a pair ofhorizontally spaced-apart elongate resilient contact structures mountedto and extending from a terminal on an interconnection substrate.

Another Horizontal Pressure Technique

In FIGS. 6A, 6B, 7A, 7B, 7C, techniques are described for effecting ahorizontal pressure connection to an elongate spring contact element 110extending from an electronic component 102 with one or more resilientcontact structures (610, 710, 711, 710′, 711′) extending from terminals(616, 716, 716′) of an interconnection substrate (614, 714). This isreminiscent of the technique described with respect to FIG. 3 wherein avertical pressure connection is made to an elongate spring contactelement 110 extending from an electronic component 102 with a resilientcontact structures (310) extending from a terminal (316) of aninterconnection substrate (314). Both techniques will effect a “soft”pressure connection.

FIG. 8 illustrates a technique 800 for effecting a “harder” temporarypressure connection to an end portion of an elongate spring contactelement 110 (only one shown in this example) extending from anelectronic component 102. In this example, an interconnection substrate814 (compare 214, 414) is provided with a plurality of through holes 834(compare 234) which are tapered to have a wider opening to receive theend 110 a of a spring contact element 110. The through holes are plated816 (compare 416) to provide terminals for contacting the end portionsof the spring contact elements 110. The through holes need only bepartially plated on one side, but are shown as being fully plated.

To effect a pressure connection between the terminals 816 and the endportion of the spring contact element 110, the tip 110 a of the springcontact element 110 is inserted from one (top, as viewed) side (surface)of the interconnection substrate 110, through the through hole 834 inthe interconnection substrate 814, so that its tip 110 a extends out theother (opposite) side of the interconnection substrate 814. Then, theinterconnection substrate 814 is moved horizontally, typically in anydirection which is parallel to the surface of the electronic component802, as indicated by the arrow 812 (compare 412) so that the narrowerwedge-like portion of the terminal 816 presses into an end portion ofthe spring contact element 110 near the tip 110 a thereof. Thiswedge-like contact concentrates force over a small contact area, therebyensuring that sufficient contact force is achieved to effect at least areliable transient pressure connection between the terminals 816 of theinterconnection substrate 814 and the spring contact elements 110 of thespringed semiconductor device 102.

In this manner, a technique is provided for making connections with endportions of elongate spring contact elements extending from asemiconductor device by:

providing an interconnection substrate with terminals which are platedthrough holes which are preferably tapered;

inserting ends of spring contact elements of a springed semiconductordevice through the through holes so that end portions of the springcontact elements are within the through holes; and

moving the interconnection substrate horizontally to effect a pressureconnection to the end portions of the spring contact elements.

Another Horizontal Pressure Technique

FIG. 8 illustrated a technique 800 for effecting a relatively “hard”wedge-like horizontal pressure connection to an end portion of anelongate spring contact element 110 extending from an electroniccomponent 102. Previously-described techniques, for example that of FIG.3, illustrate a technique 300 for making relatively “soft” verticalconnections to the ends of spring contact elements of springedsemiconductor devices. FIGS. 9A and 9B illustrate a technique 900 formaking a relatively “soft” horizontal pressure connection to the ends ofspring contact elements of springed semiconductor devices.

FIG. 9A illustrates a first step of the technique 900 wherein taperedthrough holes (one of a plurality shown) 934 (compare 834) are providedthrough an interconnection substrate 914 (compare 814). In this example,the through holes are hourglass shaped, having relatively larger areaopenings on the two opposite surfaces (top and bottom, as viewed) of theinterconnection substrate 914 and a smaller cross-sectional area at amidpoint (thicknesswise) of the interconnection substrate 914. This is adouble-tapered through hole which comes to a point within the body ofthe interconnection substrate 914.

A patterned layer 915 of sacrificial metal material such as aluminum isapplied to a one (right, as viewed) side of each through hole 934, suchas by plating. The interconnection substrate 914 can be a copper cladPCB to facilitate such plating, and a patterned layer can be plated byfirst masking the copper.

A layer 916 (compare 816) of another dissimilar metal material such asnickel is applied over the patterned layer 915. This layer 916 willconform to the pattern of the underlying layer 915. Alternatively, thelayer 915 is not patterned, and the layer 916 is applied to be patterned(e.g., by first masking the layer 915).

Next, as illustrated in FIG. 9B, the patterned sacrificial layer 915 isremoved. This is done using any suitable well-known process such asselective chemical etching, and results in terminals which aredouble-tapered “fingers” of relatively hard material (916) originatingfrom one side of the interconnection substrate 914 and extending in acantilever manner within the through holes 934. As illustrated, each ofthese finger-like terminals (916) comes to a point within the body ofthe interconnection substrate.

To effect a pressure connection between the terminals 916 and the endportion of the spring contact element 110, the tip 110 a of the springcontact element 110 is inserted from one (top, as viewed) side (surface)of the interconnection substrate 110, through the through hole 934 inthe interconnection substrate 914, so that its tip 110 a extends out theother (opposite) side of the interconnection substrate 914. Then, theinterconnection substrate 914 is moved horizontally, typically in anydirection which is parallel to the surface of the electronic component802, as indicated by the arrow 912 (compare 812) so that the point ofthe finger-like terminal 916 presses into an end portion of the springcontact element 110 near the tip 110 a thereof. This wedge-like contactconcentrates force over a small contact area, thereby ensuring thatsufficient contact force is achieved to effect at least a reliabletransient pressure connection between the terminals 916 of theinterconnection substrate 914 and the spring contact elements 110 of thespringed semiconductor device 102. The material and thickness of thematerial 916 is selected to be somewhat yielding when theinterconnection substrate 914 is urged horizontally against the springcontact elements 110 extending through the through holes.

In this manner, a technique is provided for making connections with endportions of elongate spring contact elements extending from asemiconductor device by:

providing an interconnection substrate with terminals which are elongatefinger-like terminals extending in a cantilever-like manner intodouble-tapered through holes;

inserting ends of spring contact elements of a springed semiconductordevice through the through holes so that end portions of the springcontact elements are within the through holes; and

moving the interconnection substrate horizontally to effect a pressureconnection between the terminals and the end portions of the springcontact elements.

Although the invention has been illustrated and described in detail inthe drawings and foregoing description, the same is to be considered asillustrative and not restrictive in character it being understood thatonly preferred embodiments have been shown and described, and that allchanges and modifications that come within the spirit of the inventionare desired to be protected. Undoubtedly, many other “variations” on the“themes” set forth hereinabove will occur to one having ordinary skillin the art to which the present invention most nearly pertains, and suchvariations are intended to be within the scope of the invention, asdisclosed herein.

What is claimed is:
 1. An apparatus for making electrical connectionswith an electronic device having a plurality of first elongate springcontacts extending there from, said apparatus comprising: a firstsubstrate comprising a plurality of through holes for receiving saidfirst elongate spring contacts; a second substrate secured to said firstsubstrate with a space there between; and connection means for receivingand making electrical connections with end portions of said elongatespring contact elements that extend through said through holes.
 2. Theapparatus of claim 1, herein said connection means comprises a pluralityof second spring contact elements ed on said second substrate andextending from said second substrate into said space between said firstsubstrate and said second substrate.
 3. The apparatus of claim 1,wherein said connection means comprises a plurality of second springcontact elements disposed within said space between said first substrateand said second substrate.
 4. The apparatus of claim herein saidconnection means is disposed within said space between said firstsubstrate and said second substrate.
 5. The apparatus of claim hereinsaid connection means comprises a plurality of terminals disposed onsaid second substrate.
 6. The apparatus of claim 1, wherein saidconnection means comprises a plurality of terminals formed into saidsecond substrate.
 7. The apparatus of claim 1, wherein said apparatus isa test apparatus for testing said electronic device.
 8. The apparatus ofclaim 1, wherein said second substrate comprises a printed circuitboard.
 9. The apparatus of claim 1, wherein said through holes in saidfirst substrate are tapered.
 10. The apparatus of claim 2, wherein saidsecond spring contact elements further comprise terminals disposed onends of said second spring contact elements, said terminalscorresponding to said through holes in said first substrate.
 11. Theapparatus of claim 3, wherein said second spring contact elements areelongate.
 12. The apparatus of claim 11, wherein a portion of each ofsaid second spring contact elements are disposed above and substantiallyhorizontal to said second substrate.
 13. The apparatus of claim 12,wherein an end portion of each of said second spring contact elements isdisposed to make contact with said end portions of said elongate springcontact elements that extend through said through holes.
 14. Theapparatus of claim 12, wherein an end portion of each of said secondspring contact elements is disposed in proximity to one of said throughholes in said first substrate.
 15. An apparatus for making electricalconnections with an electronic device having a plurality of firstelongate spring contacts extending there from, said apparatuscomprising: a substrate comprising a plurality of through holes throughwhich said plurality of spring contacts extend; a plurality of secondelongate spring contacts disposed on said substrate, end portions ofsaid second elongate spring contacts disposed to make electricalconnections with end portions of said first elongate spring contactelements that extend through said through holes.
 16. The apparatus ofclaim 15, wherein said end portions of said second elongate springcontacts are disposed away from said substrate and extend over at leastpart of openings in said substrate corresponding to said through holes.17. The apparatus of claim 15, wherein said second elongate springcontacts disposed on said substrate comprise pairs of spring contacts,each said pair configured to receive one of said first spring contactsextending from said electronic device.
 18. The apparatus of claim 15,wherein said apparatus is a test apparatus for testing said electronicdevice.
 19. The apparatus of claim 15, wherein said substrate comprisesa printed circuit board.
 20. An apparatus for making electricalconnections with an electronic device having a plurality of firstelongate spring contacts extending there from, said apparatuscomprising: a substrate comprising a plurality of terminals; and aplurality of second elongate spring contacts attached to said pluralityof terminals, portions of said second plurality of elongate springcontacts disposed to make electrical connections with said firstelongate spring contact elements.
 21. The apparatus of claim 20, whereinsaid second spring contact elements comprise pads disposed on ends ofsaid second spring contact elements, said pads adapted to makeelectrical connections with said first elongate spring contact elements.22. The apparatus of claim 20, wherein said portions of said pluralityof second spring contact elements are disposed above and substantiallyhorizontal to said substrate.
 23. The apparatus of claim 20, whereinsaid apparatus is a test apparatus for testing said electronic device.24. The apparatus of claim 20, wherein said substrate comprises aprinted circuit board.
 25. An apparatus for making electricalconnections with an electronic device having a plurality of elongatespring contacts extending there from, said apparatus comprising: asubstrate comprising a plurality of through holes; and a plurality ofconductive fingers formed on side walls of each of said through holes, aspacing between conductive fingers in each through hole corresponding toa thickness of each of said spring contacts along a length of each saidspring contact, said conductive fingers in each said through holethereby adapted to form a wedge-like friction connection with one ofsaid elongate spring contacts along a length of said spring contact. 26.The apparatus of claim 25, wherein each of said through holes ishour-glass shaped.
 27. The apparatus of claim 25, wherein each of saidthrough holes is tapered.
 28. The apparatus of claim 25, wherein saidapparatus is a test apparatus for testing said electronic device. 29.The apparatus of claim 25, wherein said substrate comprises a printedcircuit board.